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<FONT color="green">001</FONT>    package org.hackystat.utilities.email;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import java.util.HashSet;<a name="line.3"></a>
<FONT color="green">004</FONT>    import java.util.Locale;<a name="line.4"></a>
<FONT color="green">005</FONT>    import java.util.regex.Matcher;<a name="line.5"></a>
<FONT color="green">006</FONT>    import java.util.regex.Pattern;<a name="line.6"></a>
<FONT color="green">007</FONT>    <a name="line.7"></a>
<FONT color="green">008</FONT>    import javax.mail.internet.AddressException;<a name="line.8"></a>
<FONT color="green">009</FONT>    import javax.mail.internet.InternetAddress;<a name="line.9"></a>
<FONT color="green">010</FONT>    <a name="line.10"></a>
<FONT color="green">011</FONT>    /**<a name="line.11"></a>
<FONT color="green">012</FONT>     * Validate syntax of email addresses. Does not probe to see if mailserver exists in DNS or online.<a name="line.12"></a>
<FONT color="green">013</FONT>     * See MailProber for that. See ValidateEmailFile for an example of how to use this class.<a name="line.13"></a>
<FONT color="green">014</FONT>     * <a name="line.14"></a>
<FONT color="green">015</FONT>     * Minor reformatting.  Found in:<a name="line.15"></a>
<FONT color="green">016</FONT>     * http://www.velocityreviews.com/forums/<a name="line.16"></a>
<FONT color="green">017</FONT>     *  t128486-re-can-javamail-detect-a-nonexistant-email-address.html<a name="line.17"></a>
<FONT color="green">018</FONT>     * <a name="line.18"></a>
<FONT color="green">019</FONT>     * @author Roedy Green, Canadian Mind Products<a name="line.19"></a>
<FONT color="green">020</FONT>     * @author Philip Johnson. <a name="line.20"></a>
<FONT color="green">021</FONT>     * @version 1.0 to do: check validity of &amp; in first part of email address. Appears in practice.<a name="line.21"></a>
<FONT color="green">022</FONT>     */<a name="line.22"></a>
<FONT color="green">023</FONT>    public class ValidateEmailSyntax {<a name="line.23"></a>
<FONT color="green">024</FONT>      <a name="line.24"></a>
<FONT color="green">025</FONT>      /**<a name="line.25"></a>
<FONT color="green">026</FONT>       * Returns true if the email appears to be valid.  <a name="line.26"></a>
<FONT color="green">027</FONT>       * @param email The email address of interest. <a name="line.27"></a>
<FONT color="green">028</FONT>       * @return True if it appears to be valid. <a name="line.28"></a>
<FONT color="green">029</FONT>       */<a name="line.29"></a>
<FONT color="green">030</FONT>      public static boolean isValid(String email) {<a name="line.30"></a>
<FONT color="green">031</FONT>        return howValid(email) &gt;= 2;<a name="line.31"></a>
<FONT color="green">032</FONT>      }<a name="line.32"></a>
<FONT color="green">033</FONT>    <a name="line.33"></a>
<FONT color="green">034</FONT>      /**<a name="line.34"></a>
<FONT color="green">035</FONT>       * Check how likely an email address is to be valid. The higher the number returned, the more<a name="line.35"></a>
<FONT color="green">036</FONT>       * likely the address is valid. This method does not probe the internet in any way to see if the<a name="line.36"></a>
<FONT color="green">037</FONT>       * corresponding mail server or domain exists.<a name="line.37"></a>
<FONT color="green">038</FONT>       * <a name="line.38"></a>
<FONT color="green">039</FONT>       * @param email bare computer email address. e.g. No "Roedy Green" &lt;&gt; style addresses. No local<a name="line.39"></a>
<FONT color="green">040</FONT>       *        addresses, eg. roedy.<a name="line.40"></a>
<FONT color="green">041</FONT>       * <a name="line.41"></a>
<FONT color="green">042</FONT>       * @return 0 = email address is definitely malformed, e.g. missing @. ends in .invalid &lt;br&gt;<a name="line.42"></a>
<FONT color="green">043</FONT>       *         1 = address does not meet one of the valid patterns below. It still might be ok<a name="line.43"></a>
<FONT color="green">044</FONT>       *         according to some obscure rule in RFC 822 Java InternetAddress accepts it as valid.<a name="line.44"></a>
<FONT color="green">045</FONT>       *         &lt;br&gt;<a name="line.45"></a>
<FONT color="green">046</FONT>       *         2 = unknown top level domain. &lt;br&gt;<a name="line.46"></a>
<FONT color="green">047</FONT>       *         3 = dots at beginning or end, doubled in name. &lt;br&gt;<a name="line.47"></a>
<FONT color="green">048</FONT>       *         4 = address of form xxx@[209.139.205.2] using IP &lt;br&gt;<a name="line.48"></a>
<FONT color="green">049</FONT>       *         5 = address of form Dots _ or - in first part of name &lt;br&gt;<a name="line.49"></a>
<FONT color="green">050</FONT>       *         6 = addreess of form rare, but known, domain &lt;br&gt;<a name="line.50"></a>
<FONT color="green">051</FONT>       *         7 = address of form or any national suffix. &lt;br&gt;<a name="line.51"></a>
<FONT color="green">052</FONT>       *         8 = address of form the matching this national suffix, e.g. .ca in Canada, .de in<a name="line.52"></a>
<FONT color="green">053</FONT>       *         Germany &lt;br&gt;<a name="line.53"></a>
<FONT color="green">054</FONT>       *         9 = address of form .org .net .edu .gov ..biz -- official domains<a name="line.54"></a>
<FONT color="green">055</FONT>       */<a name="line.55"></a>
<FONT color="green">056</FONT>      private static int howValid(String email) { //NOPMD (reassign email)<a name="line.56"></a>
<FONT color="green">057</FONT>        if (email == null) {<a name="line.57"></a>
<FONT color="green">058</FONT>          return 0;<a name="line.58"></a>
<FONT color="green">059</FONT>        }<a name="line.59"></a>
<FONT color="green">060</FONT>        email = email.trim().toLowerCase();<a name="line.60"></a>
<FONT color="green">061</FONT>        int dotPlace = email.lastIndexOf('.');<a name="line.61"></a>
<FONT color="green">062</FONT>        if (0 &lt; dotPlace &amp;&amp; dotPlace &lt; email.length() - 1) {<a name="line.62"></a>
<FONT color="green">063</FONT>          /* have at least x.y */<a name="line.63"></a>
<FONT color="green">064</FONT>          String tld = email.substring(dotPlace + 1);<a name="line.64"></a>
<FONT color="green">065</FONT>          if (badTLDs.contains(tld)) {<a name="line.65"></a>
<FONT color="green">066</FONT>            /* deliberate invalid address */<a name="line.66"></a>
<FONT color="green">067</FONT>            return 0;<a name="line.67"></a>
<FONT color="green">068</FONT>          }<a name="line.68"></a>
<FONT color="green">069</FONT>          // make sure none of fragments start or end in _ or -<a name="line.69"></a>
<FONT color="green">070</FONT>          String[] fragments = splitter.split(email);<a name="line.70"></a>
<FONT color="green">071</FONT>          boolean clean = true;<a name="line.71"></a>
<FONT color="green">072</FONT>          for (int i = 0; i &lt; fragments.length; i++) {<a name="line.72"></a>
<FONT color="green">073</FONT>            if (fragments[i].startsWith("_") || fragments[i].endsWith("_")<a name="line.73"></a>
<FONT color="green">074</FONT>                || fragments[i].startsWith("-") || fragments[i].endsWith("-")) {<a name="line.74"></a>
<FONT color="green">075</FONT>              clean = false;<a name="line.75"></a>
<FONT color="green">076</FONT>              break;<a name="line.76"></a>
<FONT color="green">077</FONT>            }<a name="line.77"></a>
<FONT color="green">078</FONT>          } // end for<a name="line.78"></a>
<FONT color="green">079</FONT>          if (clean) {<a name="line.79"></a>
<FONT color="green">080</FONT>            Matcher m9 = p9.matcher(email);<a name="line.80"></a>
<FONT color="green">081</FONT>            if (m9.matches()) {<a name="line.81"></a>
<FONT color="green">082</FONT>              if (officialTLDs.contains(tld)) {<a name="line.82"></a>
<FONT color="green">083</FONT>                return 9;<a name="line.83"></a>
<FONT color="green">084</FONT>              }<a name="line.84"></a>
<FONT color="green">085</FONT>              else if (thisCountry.equals(tld)) {<a name="line.85"></a>
<FONT color="green">086</FONT>                return 8;<a name="line.86"></a>
<FONT color="green">087</FONT>              }<a name="line.87"></a>
<FONT color="green">088</FONT>              else if (nationalTLDs.contains(tld)) {<a name="line.88"></a>
<FONT color="green">089</FONT>                return 7;<a name="line.89"></a>
<FONT color="green">090</FONT>              }<a name="line.90"></a>
<FONT color="green">091</FONT>              else if (rareTLDs.contains(tld)) { //NOPMD<a name="line.91"></a>
<FONT color="green">092</FONT>                return 6;<a name="line.92"></a>
<FONT color="green">093</FONT>              }<a name="line.93"></a>
<FONT color="green">094</FONT>              else {<a name="line.94"></a>
<FONT color="green">095</FONT>                return 3; /* unknown tld */<a name="line.95"></a>
<FONT color="green">096</FONT>              }<a name="line.96"></a>
<FONT color="green">097</FONT>            }<a name="line.97"></a>
<FONT color="green">098</FONT>            // allow dots in name<a name="line.98"></a>
<FONT color="green">099</FONT>            Matcher m5 = p5.matcher(email);<a name="line.99"></a>
<FONT color="green">100</FONT>            if (m5.matches()) {<a name="line.100"></a>
<FONT color="green">101</FONT>              if (officialTLDs.contains(tld)) {<a name="line.101"></a>
<FONT color="green">102</FONT>                return 5;<a name="line.102"></a>
<FONT color="green">103</FONT>              }<a name="line.103"></a>
<FONT color="green">104</FONT>              else if (thisCountry.equals(tld)) {<a name="line.104"></a>
<FONT color="green">105</FONT>                return 5;<a name="line.105"></a>
<FONT color="green">106</FONT>              }<a name="line.106"></a>
<FONT color="green">107</FONT>              else if (nationalTLDs.contains(tld)) {<a name="line.107"></a>
<FONT color="green">108</FONT>                return 5;<a name="line.108"></a>
<FONT color="green">109</FONT>              }<a name="line.109"></a>
<FONT color="green">110</FONT>              else if (rareTLDs.contains(tld)) {<a name="line.110"></a>
<FONT color="green">111</FONT>                return 5;<a name="line.111"></a>
<FONT color="green">112</FONT>              }<a name="line.112"></a>
<FONT color="green">113</FONT>              else {<a name="line.113"></a>
<FONT color="green">114</FONT>                return 2; /* unknown tld */<a name="line.114"></a>
<FONT color="green">115</FONT>              }<a name="line.115"></a>
<FONT color="green">116</FONT>            }<a name="line.116"></a>
<FONT color="green">117</FONT>    <a name="line.117"></a>
<FONT color="green">118</FONT>            // IP<a name="line.118"></a>
<FONT color="green">119</FONT>            Matcher m4 = p4.matcher(email);<a name="line.119"></a>
<FONT color="green">120</FONT>            if (m4.matches()) {<a name="line.120"></a>
<FONT color="green">121</FONT>              return 4; /* can't tell TLD */ <a name="line.121"></a>
<FONT color="green">122</FONT>            }<a name="line.122"></a>
<FONT color="green">123</FONT>    <a name="line.123"></a>
<FONT color="green">124</FONT>            // allow even lead/trail dots in name, except at start of domain<a name="line.124"></a>
<FONT color="green">125</FONT>            Matcher m3 = p3.matcher(email);<a name="line.125"></a>
<FONT color="green">126</FONT>            if (m3.matches()) {<a name="line.126"></a>
<FONT color="green">127</FONT>              if (officialTLDs.contains(tld)) {<a name="line.127"></a>
<FONT color="green">128</FONT>                return 3;<a name="line.128"></a>
<FONT color="green">129</FONT>              }<a name="line.129"></a>
<FONT color="green">130</FONT>              else if (thisCountry.equals(tld)) {<a name="line.130"></a>
<FONT color="green">131</FONT>                return 3;<a name="line.131"></a>
<FONT color="green">132</FONT>              }<a name="line.132"></a>
<FONT color="green">133</FONT>              else if (nationalTLDs.contains(tld)) {<a name="line.133"></a>
<FONT color="green">134</FONT>                return 3;<a name="line.134"></a>
<FONT color="green">135</FONT>              }<a name="line.135"></a>
<FONT color="green">136</FONT>              else if (rareTLDs.contains(tld)) {<a name="line.136"></a>
<FONT color="green">137</FONT>                return 3;<a name="line.137"></a>
<FONT color="green">138</FONT>              }<a name="line.138"></a>
<FONT color="green">139</FONT>              else {<a name="line.139"></a>
<FONT color="green">140</FONT>                return 2; /* unknown domain */ <a name="line.140"></a>
<FONT color="green">141</FONT>              }<a name="line.141"></a>
<FONT color="green">142</FONT>            }<a name="line.142"></a>
<FONT color="green">143</FONT>          } // end if clean<a name="line.143"></a>
<FONT color="green">144</FONT>        }<a name="line.144"></a>
<FONT color="green">145</FONT>        // allow even unclean addresses, and addresses without a TLD to have a whack at passing RFC:822<a name="line.145"></a>
<FONT color="green">146</FONT>        try {<a name="line.146"></a>
<FONT color="green">147</FONT>    <a name="line.147"></a>
<FONT color="green">148</FONT>          /*<a name="line.148"></a>
<FONT color="green">149</FONT>           * see if InternetAddress likes it, it follows RFC:822. It will names without domains though.<a name="line.149"></a>
<FONT color="green">150</FONT>           */<a name="line.150"></a>
<FONT color="green">151</FONT>          InternetAddress.parse(email, true /* strict */);<a name="line.151"></a>
<FONT color="green">152</FONT>          // it liked it, no exception happened. Seems very sloppy.<a name="line.152"></a>
<FONT color="green">153</FONT>          return 1;<a name="line.153"></a>
<FONT color="green">154</FONT>        }<a name="line.154"></a>
<FONT color="green">155</FONT>        catch (AddressException e) {<a name="line.155"></a>
<FONT color="green">156</FONT>          // it did not like it<a name="line.156"></a>
<FONT color="green">157</FONT>          return 0;<a name="line.157"></a>
<FONT color="green">158</FONT>        }<a name="line.158"></a>
<FONT color="green">159</FONT>      }<a name="line.159"></a>
<FONT color="green">160</FONT>      <a name="line.160"></a>
<FONT color="green">161</FONT>     <a name="line.161"></a>
<FONT color="green">162</FONT>    <a name="line.162"></a>
<FONT color="green">163</FONT>      // allow _ - in name, lead and trailing ones are filtered later, no +.<a name="line.163"></a>
<FONT color="green">164</FONT>      private static Pattern p9 = Pattern.compile("[a-z0-9\\-_]++@[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)++");<a name="line.164"></a>
<FONT color="green">165</FONT>    <a name="line.165"></a>
<FONT color="green">166</FONT>      // to split into fields<a name="line.166"></a>
<FONT color="green">167</FONT>      private static Pattern splitter = Pattern.compile("[@\\.]");<a name="line.167"></a>
<FONT color="green">168</FONT>    <a name="line.168"></a>
<FONT color="green">169</FONT>      // to allow - _ dots in name, no +<a name="line.169"></a>
<FONT color="green">170</FONT>      private static Pattern p5 = Pattern<a name="line.170"></a>
<FONT color="green">171</FONT>          .compile("[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)*@[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)++");<a name="line.171"></a>
<FONT color="green">172</FONT>    <a name="line.172"></a>
<FONT color="green">173</FONT>      // IP style names, no +<a name="line.173"></a>
<FONT color="green">174</FONT>      private static Pattern p4 = Pattern<a name="line.174"></a>
<FONT color="green">175</FONT>          .compile("[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)*@\\[([0-9]{1,3}\\.){3}[0-9]{1,3}\\]");<a name="line.175"></a>
<FONT color="green">176</FONT>    <a name="line.176"></a>
<FONT color="green">177</FONT>      // allow dots anywhere, but not at start of domain name, no +<a name="line.177"></a>
<FONT color="green">178</FONT>      private static Pattern p3 = Pattern<a name="line.178"></a>
<FONT color="green">179</FONT>          .compile("[a-z0-9\\-_\\.]++@[a-z0-9\\-_]++(\\.[a-z0-9\\-_]++)++");<a name="line.179"></a>
<FONT color="green">180</FONT>    <a name="line.180"></a>
<FONT color="green">181</FONT>      /**<a name="line.181"></a>
<FONT color="green">182</FONT>       * build a HashSet from a array of String literals.<a name="line.182"></a>
<FONT color="green">183</FONT>       * <a name="line.183"></a>
<FONT color="green">184</FONT>       * @param list array of strings<a name="line.184"></a>
<FONT color="green">185</FONT>       * @return HashSet you can use to test if a string is in the set.<a name="line.185"></a>
<FONT color="green">186</FONT>       */<a name="line.186"></a>
<FONT color="green">187</FONT>      private static HashSet&lt;String&gt; hmaker(String[] list) {<a name="line.187"></a>
<FONT color="green">188</FONT>        HashSet&lt;String&gt; map = new HashSet&lt;String&gt;(Math.max((int) (list.length / .75f) + 1, 16));<a name="line.188"></a>
<FONT color="green">189</FONT>        for (int i = 0; i &lt; list.length; i++) {<a name="line.189"></a>
<FONT color="green">190</FONT>          map.add(list[i]);<a name="line.190"></a>
<FONT color="green">191</FONT>        }<a name="line.191"></a>
<FONT color="green">192</FONT>        return map;<a name="line.192"></a>
<FONT color="green">193</FONT>      }<a name="line.193"></a>
<FONT color="green">194</FONT>    <a name="line.194"></a>
<FONT color="green">195</FONT>      private static final String thisCountry = Locale.getDefault().getCountry().toLowerCase();<a name="line.195"></a>
<FONT color="green">196</FONT>    <a name="line.196"></a>
<FONT color="green">197</FONT>      private static final HashSet&lt;String&gt; officialTLDs = hmaker(new String[] { "aero", "biz", "coop",<a name="line.197"></a>
<FONT color="green">198</FONT>          "com", "edu", "gov", "info", "mil", "museum", "name", "net", "org", "pro", });<a name="line.198"></a>
<FONT color="green">199</FONT>    <a name="line.199"></a>
<FONT color="green">200</FONT>      private static final HashSet&lt;String&gt; rareTLDs = hmaker(new String[] { "cam", "mp3", "agent",<a name="line.200"></a>
<FONT color="green">201</FONT>          "art", "arts", "asia", "auction", "aus", "bank", "cam", "chat", "church", "club", "corp",<a name="line.201"></a>
<FONT color="green">202</FONT>          "dds", "design", "dns2go", "e", "email", "exp", "fam", "family", "faq", "fed", "film",<a name="line.202"></a>
<FONT color="green">203</FONT>          "firm", "free", "fun", "g", "game", "games", "gay", "ger", "globe", "gmbh", "golf", "gov",<a name="line.203"></a>
<FONT color="green">204</FONT>          "help", "hola", "i", "inc", "int", "jpn", "k12", "kids", "law", "learn", "llb", "llc", "llp",<a name="line.204"></a>
<FONT color="green">205</FONT>          "lnx", "love", "ltd", "mag", "mail", "med", "media", "mp3", "netz", "nic", "nom", "npo",<a name="line.205"></a>
<FONT color="green">206</FONT>          "per", "pol", "prices", "radio", "rsc", "school", "scifi", "sea", "service", "sex", "shop",<a name="line.206"></a>
<FONT color="green">207</FONT>          "sky", "soc", "space", "sport", "tech", "tour", "travel", "usvi", "video", "web", "wine",<a name="line.207"></a>
<FONT color="green">208</FONT>          "wir", "wired", "zine", "zoo", });<a name="line.208"></a>
<FONT color="green">209</FONT>    <a name="line.209"></a>
<FONT color="green">210</FONT>      private static final HashSet&lt;String&gt; nationalTLDs = hmaker(new String[] { "ac", "ad", "ae", "af",<a name="line.210"></a>
<FONT color="green">211</FONT>          "ag", "ai", "al", "am", "an", "ao", "aq", "ar", "as", "at", "au", "aw", "az", "ba", "bb",<a name="line.211"></a>
<FONT color="green">212</FONT>          "bd", "be", "bf", "bg", "bh", "bi", "bj", "bm", "bn", "bo", "br", "bs", "bt", "bv", "bw",<a name="line.212"></a>
<FONT color="green">213</FONT>          "by", "bz", "ca", "cc", "cd", "cf", "cg", "ch", "ci", "ck", "cl", "cm", "cn", "co", "cr",<a name="line.213"></a>
<FONT color="green">214</FONT>          "cu", "cv", "cx", "cy", "cz", "de", "dj", "dk", "dm", "do", "dz", "ec", "ee", "eg", "eh",<a name="line.214"></a>
<FONT color="green">215</FONT>          "er", "es", "et", "fi", "fj", "fk", "fm", "fo", "fr", "fx", "ga", "gb", "gd", "ge", "gf",<a name="line.215"></a>
<FONT color="green">216</FONT>          "gg", "gh", "gi", "gl", "gm", "gn", "gp", "gq", "gr", "gs", "gt", "gu", "gw", "gy", "hk",<a name="line.216"></a>
<FONT color="green">217</FONT>          "hm", "hn", "hr", "ht", "hu", "id", "ie", "il", "im", "in", "io", "iq", "ir", "is", "it",<a name="line.217"></a>
<FONT color="green">218</FONT>          "je", "jm", "jo", "jp", "ke", "kg", "kh", "ki", "km", "kn", "kp", "kr", "kw", "ky", "kz",<a name="line.218"></a>
<FONT color="green">219</FONT>          "la", "lb", "lc", "li", "lk", "lr", "ls", "lt", "lu", "lv", "ly", "ma", "mc", "md", "mg",<a name="line.219"></a>
<FONT color="green">220</FONT>          "mh", "mk", "ml", "mm", "mn", "mo", "mp", "mq", "mr", "ms", "mt", "mu", "mv", "mw", "mx",<a name="line.220"></a>
<FONT color="green">221</FONT>          "my", "mz", "na", "nc", "ne", "nf", "ng", "ni", "nl", "no", "np", "nr", "nu", "nz", "om",<a name="line.221"></a>
<FONT color="green">222</FONT>          "pa", "pe", "pf", "pg", "ph", "pk", "pl", "pm", "pn", "pr", "ps", "pt", "pw", "py", "qa",<a name="line.222"></a>
<FONT color="green">223</FONT>          "re", "ro", "ru", "rw", "sa", "sb", "sc", "sd", "se", "sg", "sh", "si", "sj", "sk", "sl",<a name="line.223"></a>
<FONT color="green">224</FONT>          "sm", "sn", "so", "sr", "st", "sv", "sy", "sz", "tc", "td", "tf", "tg", "th", "tj", "tk",<a name="line.224"></a>
<FONT color="green">225</FONT>          "tm", "tn", "to", "tp", "tr", "tt", "tv", "tw", "tz", "ua", "ug", "uk", "um", "us", "uy",<a name="line.225"></a>
<FONT color="green">226</FONT>          "uz", "va", "vc", "ve", "vg", "vi", "vn", "vu", "wf", "ws", "ye", "yt", "yu", "za", "zm",<a name="line.226"></a>
<FONT color="green">227</FONT>          "zw", });<a name="line.227"></a>
<FONT color="green">228</FONT>    <a name="line.228"></a>
<FONT color="green">229</FONT>      private static final HashSet&lt;String&gt; badTLDs = hmaker(new String[] { "invalid", "nowhere",<a name="line.229"></a>
<FONT color="green">230</FONT>          "noone", });<a name="line.230"></a>
<FONT color="green">231</FONT>    }<a name="line.231"></a>




























































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